Mobile messaging is a widely utilized form of communication that continues to gain in popularity. One form of mobile messaging, the short message service (SMS), has particularly contributed to rapid deployment of mobile messaging over wireless networks. SMS messaging is known in the art and is defined in EIA/TIA IS-637 versions A and B, which are hereby incorporated herein by reference in their entirety.
As with many other forms of electronic communications, mobile messaging has come to be abused by certain users of the SMS network. As explained below, spamming, i.e., the mass distribution of unsolicited communications, is of particular concern in SMS messaging.
SMS attempts to mimic real-time communications by sending a message to an intended destination as quickly as possible over the SMS network. The delivery time of SMS messaging is adversely affected by spamming because the large quantity of messages that may be associated with a single spamming event absorbs limited and valuable SMS network resources.
Moreover, most SMS messaging services charge a per-use fee, e.g., 2 cents, to a user for every message received. Thus, a recipient of a spam message will incur a cost for receiving messages the user does not want.
A common method of protecting against spamming, namely, blocking messages based on the identification of the sender, is of limited use in SMS messaging because SMS messages may be sent from an e-mail account. To circumvent such a blocking system, a spammer may easily avoid detection by simply changing his e-mail account periodically, thus effectively hiding his identity. This technique can be utilized repeatedly by a spammer because it is simple to implement and has no associated real costs when free e-mail services, e.g., Yahoo!® or Hot Mail® are utilized.
Spamming is often times used as a form of mass marketing and advertising of a particular product or service. As such, it is common for many SMS spammers to include telephone numbers with their spam messages. This feature is particularly conducive to SMS messaging because in SMS messaging a call-back number may be associated with an SMS message. Using a call-back number, a recipient of the message may dial the call-back number by simply pressing one or two buttons on their handset in order to find out more information concerning the advertised product or service. Alternately, a telephone number may be included in the text of the SMS message.
What is desired, and has heretofore been unavailable, is an effective system and method for preventing spam SMS messages from being delivered to an SMS-capable mobile devices by more accurately identifying the spam messages.